A Fixed Switching Frequency Model Predictive Control for Half-Bridge Inverter

Finite control set model predictive control has garnered significant attention in inverter control due to its compatibility with the discrete nature of power electronic systems. However, a major limitation of normal finite control set model predictive control is its inherently variable switching frequency, which fluctuates with operating conditions and system parameters. This variability poses challenges for inverter performance, complicates filter design, and increases harmonic distortion. To address these issues, this paper proposes a fixed switching frequency model predictive control method, which is based on an adaptive bandwidth-based control method that enables fixed switching frequency operation while preserving the core advantages of finite control set model predictive control. The proposed approach derives a dynamic relationship between the switching frequency and system voltage, allowing the controller to maintain a desired frequency without modifying the cost function. Simulation studies on a single-phase half-bridge inverter demonstrate that the method effectively stabilizes the switching frequency, maintains robustness against parameter variations, and achieves reliable tracking performance.